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    <!-- ## 3. 统计字符串中每个字符的个数？以对象的形式返回

   ```javascript
   var str = 'abcdacbabcbababcbabcabd'
   
   // 结果
   // { a:5， b: 出现次数, ...} -->
    <script>
        var str = 'abcdacbabcbababcbabcabd';
        var res = str.split('');
        var res1 = res.reduce(function (pre, cur) {
            if (cur in pre) {
                pre[cur] += 1;
            } else {
                pre[cur] = 1;
            }
            return pre
        }, {})
        console.log(res1)
    </script>
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